Batch CIDR Converter
The batch CIDR converter takes a list of subnets, one per line or separated by commas, and expands every one into its network address, subnet mask, usable IP range, and host count in a single table.
It accepts the three formats you are most likely to have in a spreadsheet or IPAM export: CIDR notation (10.0.0.0/24), an IP followed by a dotted mask (10.0.0.0 255.255.255.0), and bare IPs (10.0.0.5), which are treated as single hosts. Duplicate entries are removed and anything that cannot be parsed is flagged, so the tool can be pointed at raw exports without cleaning them first.
Batch CIDR Converter
Paste a list of subnets (CIDR, IP + mask, or bare IP) and convert them all to network, mask, usable range, and host count at once.
Enter values above to see results.
Frequently Asked Questions
What formats can I paste into the converter?
One subnet per line (or comma-separated), in any of three formats: CIDR notation (10.0.0.0/24), an IP address followed by a dotted-decimal mask (10.0.0.0 255.255.255.0), or a bare IP address (10.0.0.5), which is treated as a /32 single host.
How is a bare IP address converted?
A bare IP such as 10.0.0.5 is treated as a single host, or /32: its network address is itself, the mask is 255.255.255.255, and it contains one usable address.
Can I download the results?
Yes. The Download CSV button exports the full table, including the CIDR, network address, subnet mask, usable range, and host count for every subnet, in the same order shown on the page.
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